With error

- add support for `create({err | msg}, [props])`

```
    ✓ create(status) 
    ✓ create(status, msg) 
    ✓ create(props) 
    ✓ create(msg, status) 
    ✓ create(msg) 
    ✓ create(msg, props) 
    ✓ create(err) 
    ✓ create(err) with invalid err.status 
    ✓ create(err, props) 
    ✓ create(status, err, props) 
    ✓ create(status, msg, props) 
```

- remove assert. `http.request` always throw error with status -1 when connect refuse, assert here will cover up the real problem.